广州市大气气溶胶散射吸湿增长因子的观测研究

利用环境湿度的日变化,对广州市大气气溶胶散射吸湿增长因子进行了观测研究.基于反向轨迹模型HYSPLIT,将2006年7月到达广州市区的气溶胶分为海洋型、海洋/城市混合型、城市型3个类型.整个观测期间,海洋型、海洋/城市混合型、城市型气溶胶的散射吸湿增长因子f(RH=80%)的平均值分别为2.68±0.59、2.29±0.28、2.04±0.28.经验公式f(RH)=1+a(RH/100)b能够较好地拟合3种类型的气溶胶散射吸湿增长因子,海洋型、海洋城市混合型、城市型气溶胶的散射吸湿增长因子的拟合经验参数a分别为4.92、3.26、2.06,经验参数b分别为5.04、3.85、3.60.

Research on the measurement of aerosol hygroscopic growth factor in Guangzhou City

A method to calculate the aerosol hygroscopic growth factor/(RH), defined as the ratio of aerosol scattering coefficient at wet condition to that at dry condition, was proposed. Based on the back trajectory model HYSPLIT, the air masses arriving at Guangzhou in July 2006 were classified into marine, mixed and urban types, respectively. The mean value of aerosol hygroscopic growth factors at 80% RH f(RH=80%)] in Guangzhou, were 2.04±0.28, 2.29±0.28, and 2.68±0.59 for urban aerosols, mixed aerosols, and marine aerosols, respectively. The relationship between f(RH) and RH was fitted by empirical equations f(RH)=1+α(RH/100)~b and the fitting parameter a was 2.06, 3.26 and 4.92 with b being 3.60, 3.85 and 5.04 for urban aerosols, mixed aerosols, and marine aerosols, respectively.